Photographic developing-tank.



F. J. GAUKEL.

PHOTOGRAPHIC DEVELOPING TANK.

APPLICATION FILD JULY 2,1915- Patented Apr. 4, 1916.

3 SHEETSSPEET I attomug F. L GAUKEL.

PHOTOGRAPHIC DEVELOPING TANK.

APPLICATION FILED JULY 2,1915.

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F. J. GAUKEL.

PHOTOGRAPHIC DEVELOPING TANK.

APPLICATION FILED JULY 2,1915.

1 1 77,61 Patented Apr. 4, 1916.

3 SHEETS-SHEET 3.

amen Wot ,UNITED STATES PATENT OFFICE.

FRANK J'. GAUKEL, F; SAUK CITY, WISCONSIN.

PHOTOGRAPH IC DEVELOPING-TANK.

Specification of Letters Patent.

Patented Apr. 4, 1916.

Application filed July 2, 1915. Serial No. 37,719.

Improvements in Photographic Developing- Tanks, of which the followingis a specification.

This invention relates to photographic developing tanks, and one of itsobjects is to-jprovide a developing tank in which a number of negativesmay be held and sub merged in the develo ing solution, allowing theoperation of d ried on automatically without the usual process ofagitation.

A further object of the invention is to provide a developing tankwherein the negatives are held in spaced relation'to permit thedeveloping solution to come freely and uniformly in contact with all ofthe light affected surface thereof, and by means of which any individualplate may be lifted out of the solution afterward for inspection withoutthe necessity of the operator handling'the plate or dipping and. soilinghis hands in the developing solution. v

, A still further object of the invention is to provide a developingtank which is adapted to be closed light tight and may therefore beemployed for developing purprovide a tank which may also be employedposes inany place sufiiciently dark to permit insertion of--the plates,which also permits development to be carried on with color sensitiveplates in a dark 'room'without danger of light fogging while a ruby orother non-actinic light is being used, and

,which further obviates the necessity of the operator remaining indarkness during the entire developing period.

Astill further object of the invention is to for fixing and developingthe negatives in a ready, convenient and time saving manner.

The invention consists of the features of construction, combination andarrangement of parts herein fully descrlbed and claimed,

.reference being had to the accompanying drawings inv which Figure 1 isa side elevation of a developing tank embodying my invention, with thelid or cover closed. Fig. 2 is a central vertical longitudinal sectionof the same. Fig. 3 is a central vertical transverse section of thesame. Fig. 4 is a horizontal transverse section on the line H of Fig. 2.Fig. 5 is eveloping to be car ff' the tank, which is preferably ofoblong rectangular form and constructed of sheet metal, such asgalvanized sheet iron. This tank is open at the top and adapted to beclosed in a liquid, air and light tight manher by a flanged lid or cover2, provided upon the interior thereof with a sealing gasket or lining 3of rubber or other suitable.

material. Secured with this gasket to the cover by means of bolts 4; isa keeper plate 5 extending longitudinally of the cover and havingslotted end portions 6 projecting beyond the same and adapted to beengaged by locking bolts 7 hinged to the end walls of the cover andprovided with clamping nuts 8, whereby the cover may be clamped firmlyand securely in position. The tank has one of its end walls formed aboveits. horizontal center with an offset 9 provideing an interior space orchamber 10, located beyond the vertical plane of the adjacent end wallof the tank body, the interior of which body provides a developingchamber 11 to receive the developing solution. The plates 12'to bedeveloped are adapted to be held in spaced relationiwithin the chamber11, holders 13 being provided to receive the plates and slidably supportthem in spaced relation to each other. Each of said holders comprises aU-shaped frame open at the top and embodying side bars and a crossbarconnecting said side bars at their lower ends, said bars 1 being groovedor channeled to slidably receivethe side and lower end edges of theplate fitted therein, so that the plate may be slidably inserted andremoved in an obvious manner. The holders 13 are removably and slidablyfitted in grooved guideways 14 in guide plates 15, removably disposedwithin the tank and arranged against or in proximity to the end wallsthereof, the guide plate at the end of the tank having the offsetchamher being relatively shorter than' 'the other.

guide plate for an obvious purpose. These guide plates may receive kitsor auxiliary guide members, adapted to hold plates of different sizes,or the plate holders may be constructed for that purpose with inserts,

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so that plates of the same size or of different sizes may be developedsimultaneously. By thus mounting and holding the plates in spacedrelation, it will be evident that all that they may be normally heldsubmerged in the solution but may be projected upward at the will of theoperator in order that the operator may observe the plate to determinethe extent ofthe development process. As shown in the present instance,each holder has its cross bar provided with a bowed ellipticalprojecting spring 16, and has one of its side bars provided with a lugor shoulder 17. The holder is adapted to be forced down in the guidegrooves of the guide plates, to compress the spring, allowing the platecarried by the holder to be depressed until fully submerged in thedeveloping solution. For the purpose of fastening the holders indepressed position, latches 18 are provided to engage the lugs orshoulders 17, and these latches are vertically disposed within theopposite chamber or compartment 10 and mounted upon a pivot rod or bolt19 with spacing washers 20 therebetween, coiled springs 21 being alsoemployed to hold the latches in normal position. The lower ends oftheselatches are adapted to be projected into and out of the path of the lugsor shoulders 17 whereby the holders 13 may be locked in depressedposition,- but by retracting its holding latch any desired holder may bereleased so that the associated spring 16 will project the vholderupward in the guideway to expose a portion of the plate to the View ofthe .operator, in order that he may observe the course of development.

The upper ends of the latches 18 project upward through and are movablein guide slots 22 in a retaining plate 23 secured to the outer wall ofthe compartment 10,

whereby the upper ends of the latches are held properly spaced so thatthey may be engaged for manipulation bv the thumb or finger of theoperator. Aflanged plate 24 may be secured within the chamber 10 toserve as a stop to limit the retracted movement of the latches, thusadapting the latches to have a certain amount of operating motion only.-Thus it will be understood that when the plates to be developed arearranged in their holders and the latter fitted'within the tankcontaining the developing solution, the cover may be closed to seal thetank securely and exclude all light rays, allowlng the developingoperation to proceed, the progress of which may be viewed from time totime by removing the lid or cover and inspecting any or all of theplates. Inasmuch as the time required to insert the plates within theirholders, and the latter within the'tank is comparatively short, and asthe plates are pro-.

tected within the tank against all light rays, it is evident that eventhe most sensitive plates may be handled and 1 developed without dangerof light fogging, as the plates need only be exposed to dim rays from aruby or other non-actinic light for an extremely short period.Furthermore, as the plates are in darkness during the entire period ofdevelopment, the operator in the dark room need-not remain in completedarkness, but may turn on the light so that other work may be performedwhile the plates are under development.

The guide plates are provided with p'erforations 25 for the flow offluid therethrough, and the tank is provided in the outer wall of theoffset portion thereof with a discharge outlet 26 normally closed byascrew cap 27, and through which the fluid contents ofthe tank may bedischarged at the completion of a developing, fixing or washingoperation. At the opposite side of the tank is an inlet 27 for thesupply of wash water which may flow through the tank and outward via theoutlet 26, whenit is desired to wash the negatives after they have beenfixed. This inlet 27" is norand thus introduced into the tank, or sothat water from a faucet or other source of sup- 'ply may be conductedto the tank.

It will thus be understood that the device may be employed for: fixingthe negatives 'after development, and thereafter for washing thenegatives clear of the fixing solution. The advantages-of the device inother respects, are its simplicity-and capability of being furnished ata low cost to both professional and amateur photographers, itsadaptability for the several uses specified, and its cleanliness andconvenience in enabling the plates and negatives to be handled withouttrouble or discomfort.

I claim 1. A device of the characterdescribed comprising a tank, plateholders movabl mounted in the tank, means for holding the holdersdepressed to keep the plates confined in a solution therein, and meansfor releasing and projecting the holders to expose the plates forinspection.

2. A device of the character described' comprising a tank, guides uponthe interlor of the tank, channeled plate holders mounted in saidguides, springs for projecting the holders upward, and latches forholding the holders depressed and releasing them for upward projection.

' 3. A device of the character described comprising a tank, groovedguideways upon the interior of the tank, channeled holders slidablymounted in said guides, springs carried by the holders for projectingthe holders upward, and latches for holding said holders depressedagainst the resistance of said springs and releasing the holders forupward projection by the springs.

4. A device of the character described comprising a tank, groovedguideways upon the interior of the tank, grooved plate holders slidablymounted in said guideways, springs for projecting the holders upward,and pivoted latch devices to engage and hold said holders depressedagainst the resistance of the springs and adapted to release saidholders for upward projection.

5. A device of -the character described comprising a tank, groovedguideways upon the interior of the tank, grooved plate holders' slidablymounted in said guideways, bowed elliptical springs upon the bases ofthe holders for projecting the holders upward, and adapted to betensioned when the holders are depressed, and pivoted latches formaintaining said holders depressed and adapted to effect the release ofsaid holders for projection.

6. A device of the character described comprising a tank having anoffset compartment at the upper portion thereof, guideways upon theinterior of the tank, channeled holders slidably mounted in saidguideways, springs adapted to be tensioned when the holders are insertedin the guideways for subsequently projecting said holders, and latchespivotally mounted in said compartment and adapted to engage the holdersto maintain them depressed and to be moved out of engagement with theholders to permit projection thereof.

In testimony whereof I 'afiix my signature inpresence of two witnesses.

FRANK J. GAUKEL.

\Vitnesses LoUIs H. GUHL, EDWIN J. FARR.

